The specific aims for this proposal are: 1. To determine the nature of the binding of well characterized lipopolysaccharide (LPS) preparations to isolated bone cells. 2. To determine the effect of well characterized LPS preparations from potential periodontopathic organisms on bone-collagen synthesis and bone resorption. 3. To determine the effects of lipoprotein (LP) from bacterial cell walls and lipid A associated protein (LAP) on bone resorption and bone-collagen synthesis. The long term objective is an understanding on the molecular level for the action of bacterial amphiphiles on bone resorption and deposition. The methodology to be used involves bones in organ culture and the binding of labeled LPS to bone cells.